{
 "cells": [
  {
   "cell_type": "markdown",
   "id": "b16ab89a",
   "metadata": {},
   "source": [
    "# 上周回顾\n",
    "> 1.函数的定义：def  \n",
    "> 2.函数名的定义规则-->变量名一样的规则  \n",
    "> 3.调用函数的方式：func_name(参数)  \n",
    "> 4.参数：  \n",
    ">> 1.形式参数（定义函数）  \n",
    ">> 2.实际参数（调用函数）  \n",
    ">> 3.有多个参数时：  \n",
    ">>> 1.关键字参数  \n",
    ">>> 2.位置参数（调用函数时）---> 关键字参数要均放在末尾（多个不考虑顺序）  \n",
    ">>> 3.默认参数（定义函数时）---> 默认参数均放在末尾（多个不考虑顺序）  \n",
    "\n",
    "# 本周知识\n",
    "\n",
    "> 1. 函数的返回值  \n",
    "> 2. 函数的输入参数类型  \n",
    "> 3. 函数的返回参数类型  \n",
    "> 4. 模块的概念  \n",
    "> 5. 如何创建一个模块，并且调用自己定义的模块  "
   ]
  },
  {
   "cell_type": "markdown",
   "id": "b8a98fdc",
   "metadata": {},
   "source": [
    "## 函数的返回值\n",
    "> 1.返回值关键字：return  \n",
    ">> 1.函数一定有返回值（无论是什么编程语言）  \n",
    ">> 2.在其他的编程语言中（如c语言，java等），返回值一定要写，不写会报错！；对于python（更高级的语言），返回值如果不写，给定默认值None  \n",
    ">> 3.返回值一般为函数体运行的结果（result）（函数返回值实践1）；也可以是自定义的函数返回值（实践2）  "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "id": "af78c15f",
   "metadata": {},
   "outputs": [],
   "source": [
    "# 函数返回值实践1\n",
    "def get_formatted_name(first_name,last_name):\n",
    "    \"\"\"返回整洁的姓名\"\"\"\n",
    "    full_name = first_name + ' '+ last_name\n",
    "#    print(full_name) print只是函数打印的结果，以后用return\n",
    "    return full_name # 函数运算结果"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "id": "eef0eebb",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Li Hua'"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "get_formatted_name(\"Li\",\"Hua\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "id": "ed685466",
   "metadata": {},
   "outputs": [],
   "source": [
    "# 函数返回实践2\n",
    "def log_in(username,password):\n",
    "    \"\"\"验证登录信息\"\"\"\n",
    "    if username == \"Lihua\" and password ==123456:\n",
    "        return 1\n",
    "    else:\n",
    "        return 0"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "id": "1160ed21",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "log_in(\"Lihua\",1234567)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "c1ec38dc",
   "metadata": {},
   "source": [
    "# 函数的输入参数类型\n",
    "> 1.函数在调用过程中可以输入复杂的参数（例如列表、字典、集合、元组等）：  \n",
    ">> 1.函数参数为列表  \n",
    ">> 2.函数参数为字典  \n",
    ">> 3.... \n",
    "\n",
    "> 2.函数可以输入不确定个数的参数：  \n",
    ">> 1.*args  \n",
    ">>> 1.args 可以接受多个数据（单值）  \n",
    ">>> 2.args 将多个数据存在一个元组当中，实际还是一个变量  \n",
    "\n",
    ">> 2.** kwargs  \n",
    ">>> 1.kwargs 可以接受多个数据(键值对)==> 关键字参数  \n",
    ">>> 2.kwargs 将多个 键值对 的数据存放在一个 字典 中，实际上还是一个变量  "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "d02fa05a",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "id": "a110e578",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test_A(names):\n",
    "    \"\"\"测试函数参数输入为列表\"\"\"\n",
    "    return names"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "id": "a664f0b9",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['Lihua', 'Alex', 'Ziqi']"
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test_A([\"Lihua\",\"Alex\",\"Ziqi\"])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "id": "89fec3f0",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test_B(person):\n",
    "    \"\"\"测试函数参数输入为字典\"\"\"\n",
    "    return person"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "id": "88a21ed5",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'stu_id': 210001, 'age': 18, 'Job': 'student'}"
      ]
     },
     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test_B({\"stu_id\":210001,\"age\":18,\"Job\":\"student\"})"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "bf029db7",
   "metadata": {},
   "source": [
    "> 1.函数可以输入不确定个数的参数：\n",
    "*args\n",
    "args 可以接受多个数据（单值）\n",
    "args 将多个数据存在一个元组当中，实际还是一个变量\n",
    "** kwargs\n",
    "kwargs 可以接受多个数据(键值对)==> 关键字参数\n",
    "kwargs 将多个 键值对 的数据存放在一个**字典**中，实际上还是一个变量"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "id": "2bb6789b",
   "metadata": {},
   "outputs": [],
   "source": [
    "def food_ingred(food,*ingreds):\n",
    "    \"\"\"食物配料单\"\"\"\n",
    "    return food,ingreds"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "bae4cdf7",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "('pizza', ('mushroom', 'green peppers', 'extra cheese'))"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "food_ingred(\"pizza\",\"mushroom\",\"green peppers\",\"extra cheese\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "71a44275",
   "metadata": {},
   "outputs": [],
   "source": [
    "def person(stud_name,**stud_course):\n",
    "    \"\"\"学生个人信息完善表\"\"\"\n",
    "    return stud_name,stud_course"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "id": "54eb782b",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "('Lihua', {'course_星期一': 'API', 'course_星期二': 'app原型设计'})"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "person(\"Lihua\",course_星期一=\"API\",course_星期二=\"app原型设计\")"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "45a7e9ea",
   "metadata": {},
   "source": [
    "#  函数的输出（返回值）参数类型\n",
    " \n",
    "> 1.在编程语言中，函数的返回值只能是一个值  \n",
    "> 2.返回值可以是 字符串、数值、列表、字典等数据（单一值）  \n",
    "> 3.python可以输出多个返回值，结果会用一个元组进行封装并返回。（本质不违背函数的定义）"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "id": "ddf943ce",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test1_return():\n",
    "    \"\"\"测试返回值return为字符串\"\"\"\n",
    "    return \"你好\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "id": "bd1be26e",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'你好'"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test1_return()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "id": "04708423",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test2_return():\n",
    "    \"\"\"测试返回值return为数值\"\"\"\n",
    "    return 1234"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "id": "cea0c9a8",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "1234"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test2_return()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "id": "bf7db1f7",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test3_return():\n",
    "    \"\"\"测试返回值return为字典\"\"\"\n",
    "    return {'stud_id':2001,'age':18}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "id": "ee8fd7e3",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'stud_id': 2001, 'age': 18}"
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test3_return()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "id": "6d978aa5",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test4_return():\n",
    "    \"\"\"测试返回值return为列表\"\"\"\n",
    "    return ['ha','he','hw']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "id": "a10a840a",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['ha', 'he', 'hw']"
      ]
     },
     "execution_count": 20,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test4_return()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "id": "0c5e8b68",
   "metadata": {},
   "outputs": [],
   "source": [
    "# ******** return 后面写多个值，将会返回一个元组（一个值，不违背函数在编程思维中的定义）\n",
    "def test5_return():\n",
    "    \"\"\"测试返回值return 为 多个值的情况\"\"\"\n",
    "    return 18,\"Lihua\",['Lihua', 'Alex', 'Ziqi'],{'stud_id': 210001, 'age': 18, 'Job': 'student'}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "id": "ef90a7b7",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(18,\n",
       " 'Lihua',\n",
       " ['Lihua', 'Alex', 'Ziqi'],\n",
       " {'stud_id': 210001, 'age': 18, 'Job': 'student'})"
      ]
     },
     "execution_count": 28,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test5_return()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "id": "a2297b7c",
   "metadata": {},
   "outputs": [],
   "source": [
    "def test6_return():\n",
    "    \"\"\"测试返回值return为 多个值的情况\"\"\"\n",
    "    return 88,98,45"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "id": "7ff306eb",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(88, 98, 45)"
      ]
     },
     "execution_count": 26,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "test6_return()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "3dd3491e",
   "metadata": {},
   "source": [
    "# 模块\n",
    "> 1.使用模块可以隐藏函数的源代码  \n",
    "> 2.使用的人不需要会底层代码（只需要会使用模块即可）  \n",
    "> 3.模块的使用的方法：  \n",
    ">> 1.import 模块名  \n",
    ">>> *使用： 模块名.函数名()  \n",
    "\n",
    ">> 2.from 模块名 import 函数名  \n",
    ">>> *使用： 函数名()  "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "id": "168691da",
   "metadata": {},
   "outputs": [],
   "source": [
    "import study"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "id": "9e1793c5",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'e', 'o', 'u'}"
      ]
     },
     "execution_count": 34,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 函数的调用\n",
    "study.search4vowels(\"hello foru\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "id": "cd27780a",
   "metadata": {},
   "outputs": [],
   "source": [
    "import time \n",
    "# 直接调用整个模块，这在不确定该用哪个函数时\n",
    "# 缺点：占内存"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "id": "b56f54c6",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "time.struct_time(tm_year=2021, tm_mon=12, tm_mday=9, tm_hour=23, tm_min=3, tm_sec=26, tm_wday=3, tm_yday=343, tm_isdst=0)"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "time.localtime()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "id": "b672baae",
   "metadata": {},
   "outputs": [],
   "source": [
    "from time import localtime \n",
    "# 只单一调用某个函数，这在明确需要哪个函数时\n",
    "# 缺点：每次调用前都需要写from"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "54e2230d",
   "metadata": {},
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "e48ccdc9",
   "metadata": {},
   "outputs": [],
   "source": []
  }
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   "title_cell": "Table of Contents",
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